As Italy outplayed England in Kiev, the man who has contributed so much to this beguiling Azzurri side was somewhere else, with the cloud of match-fixing hanging over him. Antonio Conte took over as Juventus manager last summer and in less than a year he transformed the fortunes and careers of, among others, Leonardo Bonucci, Andrea Barzagli, Claudio Marchisio and Andrea Pirlo, now key players in Cesare Prandelli's Italy team.

Juventus had not won a league title – at least not one they had been allowed to keep – since 2003 when Conte took over. They were not even among the favourites to win the scudetto last season, with Milan and Internazionale expected to battle it out at the top, but in the end they went through the season unbeaten. Fifteen days after the final game of the league season, however, the sky fell in and Conte was named as part of the latest investigation into match-fixing.

The midfielder Filippo Carobbio claimed that Conte was aware of two incidents of match-fixing while coach at Siena during the 2010-11 season, even telling the players that they "didn't need to worry" about the game against Novara as it had been taken care of.

The 42-year-old denies the allegations and said at the end of May: "My history as a football player and coach speaks for itself: you can ask my team-mates, my players and my opponents. But for all my honesty and integrity, I have been attacked with sticks."

With all this as a backdrop, the Juventus players at Euro 2012 are doing an extraordinary job of going about their business. There has often been a strong Juve presence at World Cups and European Championships. When Italy won the World Cup in 1982, there were six Bianconeri players on the pitch, and on that magical night in Berlin six years ago there were nine altogether (six for Italy and three for France). In one of the best Italy teams of all time, in 1978, there were nine.

The Azzurri have often been tinged with black and white; the difference this time is that the players are less well-known. In fact, some of them may not even have been close to a call-up if it had not been for Conte. Take Marchisio, who in one season has gone from an undoubted but untried talent to become one of Europe's best midfielders. When coming through the Juve youth system, the first thing he did was to ask his hero Alessandro Del Piero for an autograph. Marchisio was compared to the legendary Marco Tardelli early on but, having been born in 1986, he did not know who Tardelli was and how much of a compliment it was . "I went on to YouTube to have a look at Tardelli and … well, yeah, maybe he is similar to me in some movements. But I prefer Steven Gerrard."

Marchisio made his debut for Juve in Serie B in October 2006 following that year's match-fixing scandal but after winning promotion back to Serie A, he was loaned out to Empoli together with his good friend Sebastian Giovinco. For years, Marchisio was not even deemed to be the better of the two, never mind being on the cusp of an international breakthrough. Last season, however, he missed only two league games as Juventus had their Invincibles campaign.

After winning the title, he hailed Conte's influence on himself and the rest of the squad. "I have dreamed about this moment since I got into the first team, especially after the last two years, which, frankly, have given both players and fans stomach aches. There is no question about the coach being the architect of this success, he has given the squad new life, he provided a turning point and gave us an identity.

"The Juve players have brought the continuity and the desire to win with them to this Italy team. It is a desire that we have deep inside us and one we have taken with us to Poland and Ukraine."

Marchisio also showed that there are more progressive individuals than Antonio Cassano in the Italy squad, having come out in favour of same-sex marriage in an interview with Vogue. "I agree with people of the same sex being able to marry each other. But in our environment [football] the topic is still a bit taboo. If someone comes out at their workplace, it doesn't create a problem, but it is difficult to imagine it in a football team. It is not fair."

Bonucci, who has not only looked assured at the back at Euro 2012 but also silenced Mario Balotelli after the striker was venting his anger following the goal against Republic of Ireland, has had a similarly rocky road to success. Only three seasons ago he was part of an emerging central defensive partnership with Andrea Ranocchia. As with Marchisio and Giovinco, however, Bonucci was deemed to be the lesser player of the two. In 2010, Juventus and Inter tried to sign both defenders.

Ranocchia ended up in Milan and Bonucci was sold to Juventus, leading to a unanimous verdict by the experts: Inter had done well, Juventus had lost out. They were convinced they were right until last winter, when Ranocchia was benched by Inter and Bonucci became a regular for Juventus, controlling every game together with Pirlo, who had joined from Milan.

Just a year ago, in fact, Juventus were prepared to sell Marchisio and Bonucci. However, Conte blocked the transfer and built his 3-5-2 around them (and Pirlo of course). That was the moment Juventus's destiny changed, and in a certain way, Italy's too. It rejuvenated Pirlo and Andrea Barzagli, who was called a "pensioner" when he joined Juve from Wolfsburg as a 29-year-old in January 2011. Last October, when Prandelli called him up for the crucial qualifier against Serbia, his first reaction was: "I can't believe I am here again. I thought I was out for ever."

The season before Conte arrived, Barzagli, Bonucci and Giorgio Chiellini were part of a terrible defence that leaked 56 goals in 38 matches. Last season, they conceded only 20 goals. Same players but very different results. They had never played in a three-man defence before but adapted superbly and thus were perfectly prepared when Prandelli opted for 3-5-2 against Spain in the opening game of Euro 2012. It did not matter that it was Roma's Daniele De Rossi who joined Chiellini and Bonucci in defence in that 1-1 draw. The Juve players have a telepathic understanding these days, making the transition from midfield to defence an easy one for De Rossi.

No one could have imagined such a Juve-dependent Azzurri 12 months ago. No one but Conte.